1. Field of the Invention:
The present invention relates to an image pick-up device suited for one shot image pick-up, particularly, a picture recording device with improved efficiency and able to provide improved picture quality by use of a solid image sensor in combination with a shutter.
2. Description of the Prior Art:
Until now in the case of video cameras using a solid stage image sensor, such as a CCD, the storage, transfer and reading out of the image are carried out at a certain predetermined period.
Consequently, the storage time is constant so that the quality of the picture degrades depending on adverse conditions of an object, such as when the object has a quick motion or high brightness.
Further, even in the case of the conventional frame transfer type CCD, for example, when a strong light falls incident on the light sensing part while the charge formed in the light sensing part is being transferred to the storage portion, the light is superposed on the charge during the transfer as noise over a wide range, which causes a smear phenomenon and degraces the picture quality.
Further, in the case of an interline transfer type CCD, although the vertical shift register is shaded, thereby light of long wavelength falls obliquely incident upon the substrate under the vertical shift register so as to produce minority carries so that there is a possiblity of smear in the same way. Particularly, in the case of the interline transfer type, the charge in the vertical register is normally transferred by 1 bit at every horizontal period of the TV signal so that the above problem is very likely to take place.
Further, the device in which an overflow drain gate is provided beside each picture element so as to cut out the charge in the light sensing part in order to control the storage timing and the storage time of the photo electrons and to transfer the stored charge periodically, is known.
In this way, it is possible not only to read out the signal at the TV rate but also to optionally set the storage time. However, if the storage time is shortened in this case, the S/N becomes remarkably inferior as described above in case smear takes place during the charge transfer.
Further, the conventional video camera is designed for continuous photographing and a satisfactory image signal cannot be obtained if only one shot is desired to be photographed.
Further, when the image pick-up device is provided with a video monitor, it is impossible to confirm the one shot picture image.